<template>
  <div class="article-container">
    <!-- 导航栏 -->
    <van-nav-bar
      class="page-nav-bar"
      left-arrow
      title="黑马头条"
      @click-left='$router.back()'
    ></van-nav-bar>
    <!-- /导航栏 -->

    <div class="main-wrap">
      <!-- 加载中 -->
      <div class="loading-wrap" v-if="resultCode === 1">
        <van-loading
          color="#3296fa"
          vertical
        >加载中</van-loading>
      </div>
      <!-- /加载中 -->

      <!-- 加载完成-文章详情 -->
      <div class="article-detail"  v-if="resultCode === 2">
        <!-- 文章标题 -->
        <h1 class="article-title">{{ article.title }}</h1>
        <!-- /文章标题 -->

        <!-- 用户信息 -->
        <van-cell class="user-info" center :border="false">
          <van-image
            class="avatar"
            slot="icon"
            round
            fit="cover"
            :src="article.aut_photo"
          />
          <div slot="title" class="user-name">{{ article.aut_name }}</div>
          <div slot="label" class="publish-date">{{ article.puddate | relativeTime }}</div>
          <van-button
            class="follow-btn"
            type="info"
            color="#3296fa"
            round
            size="small"
            icon="plus"
            v-if="is_followed = true"
          >关注</van-button>
          <van-button
            class="follow-btn"
            round
            size="small"
            v-else
          >已关注</van-button>
        </van-cell>
        <!-- /用户信息 -->

        <!-- 文章内容 -->
        <div class="article-content" v-html="article.content" ref="content"></div>
        <van-divider>正文结束</van-divider>
      </div>

            <!-- 底部区域 -->
      <div class="article-bottom">
        <van-button
          class="comment-btn"
          type="default"
          round
          size="small"
        >写评论</van-button>
        <van-icon
          name="comment-o"
          badge="123"
          color="#777"
        />
        <van-icon
          color="#777"
          name="star-o"
        />
        <van-icon
          color="#777"
          name="good-job-o"
        />
        <van-icon name="share" color="#777777"></van-icon>
      </div>
      <!-- /底部区域 -->

      <!-- /加载完成-文章详情 -->

      <!-- 加载失败：404 资源不存在-->
      <div class="error-wrap"  v-if="resultCode === 3">
        <van-icon name="failure" />
        <p class="text">该资源不存在或已删除！</p>
      </div>
      <!-- /加载失败：404 -->

      <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
      <div class="error-wrap"  v-if="resultCode === 4">
        <van-icon name="failure" />
        <p class="text">内容加载失败！</p>
        <van-button class="retry-btn">点击重试</van-button>
      </div>
      <!-- /加载失败：其它未知错误（例如网络原因或服务端异常） -->
    </div>

  </div>
</template>

<script>
import { getArticleById } from '@/api/article'
import { ImagePreview } from 'vant'
export default {
  name: 'ArticleIndex',
  components: {},
  props: {
    articleId: {
      type: [Number, String, Object],
      required: true
    }
  },
  data () {
    return {
      article: {},
      resultCode:1
    }
  },
  computed: {},
  watch: {},
  created () {
    this.loadArticle()
  },
  mounted () {

  },
  methods: {
  
    async loadArticle(){
      // 加载中
      this.resultCode=1
      try {

       const { data: res } = await getArticleById(this.articleId)
        this.article = res.data
        console.log(res)
        // 加载完成后
        this.resultCode = 2
        // 渲染图片预览的方法
        this.loadPhoto()
      } catch (error) {
        this.$toast.fail('获取文章详情失败')
        if(error.response.status === 404){
          // 如果资源不存在
          this.resultCode = 3
        }else{
          // 加载失败其他的数据类型错误
          this.resultCode = 4
        }
        
      }
    },
    loadPhoto() {
      // 获取到img的dom元素 但是需要在加载完成之后并且dom已经渲染完成才能重新获取img的dom元素
      this.$nextTick(() =>{
        let imgNodes = this.$refs.content.getElementsByTagName('img')
        imgNodes = Array.from(imgNodes)
        const imgUrl = imgNodes.map(val =>val.src)
        console.log(imgUrl)
        // 对imageNodes进行遍历
        imgNodes.forEach((img, index) => {
          img.onclick = function () {
            ImagePreview({
               images:  imgUrl,
              startPosition: index
            })
          }
        })
      })
    }
  }
}
</script>

<style scoped lang="less">
@import url('./github-markdown.css');
.article-container {
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    background-color: #fff;
  }
  .article-detail {
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }

    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }

    .article-content {
      padding: 55px 32px;
      /deep/ p {
        text-align: justify;
      }
    }
  }

  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }

  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }

  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
    .van-icon {
      font-size: 40px;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
  }
}
</style>